The only native Welsh plum variety, it is thought to have been cultivated by medieval monks, according to local research. The early fruit have large, sweet, dark-red fruit that are strewn with golden dots.
Local fruit-tree grower Ian Sturrock said: "It's a little-known variety but it could help put Denbigh on the map." The north Wales town has already established an annual plum festival in recent years.
A dossier has been drawn up by development agency Cadwyn Clwyd. This is due to be scrutinised by Defra before being passed for action by the European Commission.
Armagh Bramley apples, Kentish cobnuts and Fenland celery are among other produce to have recently been granted PGI status.